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Stem Cell ACL: Cutting-Edge Knee Repair Sans Surgery

I entered the room where a Halloween-prop-sized needle was being cored down into the patient’s hip still skeptical that this procedure was “comfortable” and “painless” as I had read. But, after carrying on a conversation with the patient—who was, admittedly, doing much better than I at that moment, chatting calmly about feeling only pressure as the needle filled with blood—I exited the room a believer.

Let me back up a bit. A torn ACL is a more or less a sentence for:

A) Surgery and at least a six-month recovery time

B) Weight training to the point of forming Hulk-like hamstrings strong enough to keep the knee from hyperextending—in other words, perform the ACL’s job

This particular patient opted for procedure C… or rather, R for Regenexx, an alternative to traditional orthopedic surgery. What I witnessed that queasy morning was the stem cell aspiration step of the Regenexx process wherein doctors extract the richest concentration of stem cells from your hip’s bone marrow.

No epidural block, either. Dr. Centeno and team at the Denver-based Centeno Schultz Clinic are able to carry out this procedure—currently most commonly used to treat torn ACL and rotator cuff injuries, knee arthritis or low back pinched nerve—relatively pain free after reportedly perfecting the numbing process. But the cool part is what happens next.

The stem cell aspiration step of the Regenexx process looks a lot worse than it feels.

Copyright: Heather B. Fried

Mend Minions

“To concentrate stem cells, the bone marrow aspirate is first removed and then centrifuged several times,” according to Dr. Chris Centeno, clinic proprietor. “Two layers rich in stem cells are pulled off and then injected back into the patient.” Sent straight to where they’re needed most via imaging guidance, these little mend minions—chameleon-like cells that can morph to specialize throughout the body—get to work repairing the tear. “They know where to go and what to do—as long as they are placed accurately,” Centeno explains.

As to why this should be like music (or, say, the sound of avy bombs in the distance) to a knee-injury-prone skier’s ears? Medically and anatomically speaking, our original ACL equipment “goes in at about a 45-degree angle, and so it’s really good at preventing this tibia from moving forward,” Centeno points out as he draws a whiteboard diagram that shows how, on the flipside, a surgical ACL’s angle makes it already inferior to the job at hand. “So anything we can do to get an ACL to heal in its normal, physiologic position is probably going to be better long term than an ACL that goes in at a much steeper position because we have to have those graft tunnels to be able to anchor it.”

Dr. Centeno illustrates the difference between native and surgical ACLs.

Copyright: Heather B. Fried

That’s the point Centeno is most intent on driving home. But what likely resonates even more with skiers is a recovery time that, in some cases, could have you back on the slopes that very same season with a theoretical three- to six-month window. “Unlike a surgical ACL, there is less down time and atrophy, so return to high level activities goes much more quickly as half of the rehab isn’t focused on getting back what was lost,” Centeno reports. “In addition, a Regenexx patient may continue non-cutting activities, like an elliptical trainer, for example, almost immediately after the procedure. This way they are able to maintain fitness while the knee is healing,” he goes on. Traditional ACL reconstruction usually means dealing with crutches, healing the repaired knee and the damage done to the tissue during surgery, all while managing atrophied muscles.

Stem Cell-Able

At any rate, physical therapy (i.e. the hard part) between procedures is similar, and not all patients heal this quickly… assuming Regenexx is recommended to begin with.

“The ideal candidate depends on condition,” says Centeno. According to their clinical registry, partial or complete non-retracted ligament tears (those that aren’t pulled back with large gaps) respond well to the same-day injection-based procedure. In other cases, patients are advised to head to Europe or Grand Cayman where the more involved stem cell culturing process isn’t prohibited like it is in the U.S.

“If culturing is needed, these concentrates are plated onto flasks where the stem cells are selected from other cells by adherence to the flask,” Centeno says. “The cells are fed with the growth factors from the patient’s own platelets and then grown to bigger numbers. They can then either be frozen for future use or re-injected into the same patient.” Stateside, this two-month process creates what’s considered to be a "new drug" and a major FDA no-no.

ACL in Action

Thankfully for DPS Skis Founder and pro skier, Stephan Drake, who’s no stranger to “medical tourism,” ACLs do just fine with the uncultured stem cell count. Drake blew his ACL skiing while filming in Alaska. Two injection series and just over a year later, his stem-cell-restored ACL is “holding up this season so far! It feels stable... still some pain, but I think that's more related to my meniscus,” he says of the repercussions of just one in a series of older injuries—as the foregone conclusion often goes with skiers at his level. In fact, he attributes prior damage to his hip and ankle as a factor limiting his most recent Regenexx rehab process.

DPS Founder, Stephan Drake, enjoying the spoils of being injury free before blowing out his ACL and undergoing Regenexx.

Copyright: Oskar Enander

But still, Drake considers Centeno’s procedure a success—a sentiment he similarly holds for Dr. Milne Ongley’s treatment, another alternative to traditional surgery he underwent years back for crash-caused partial ACL, MCL and meniscus tears. Located in Ensenada, Mexico, the somewhat obscure-sounding Ongley Institute is actually well known in ski circles, treating world-class athletes from the likes of Bode Miller and Erik Schlopy with an injection-based biologic regenerating solution. According to the website, said solution is designed to stimulate the body's own healing mechanisms. “I went down to him in ’09, and I was back on snow six months later—full blast,” Drake reports. “So I had a really good result there, and then that’s what led me, when I tore my ACL this time, to consider alternative methods of treatment.”

Drake reiterates his belief that former injuries contributed to his ongoing pain and less than ideal recovery time, even when his MRI results pointed to an intact ACL back in the spring—long before he felt ready to click into skis again. “It has some scarring from a previous injury, but it’s in one piece whereas when I tore it a year ago, it was a full grade-three ACL tear, so it was in two pieces.”

Although Drake describes the Regenexx reinjection process as one that, at times, reaches a considerable level of pain, he’ll take this less invasive method over the alternative’s potential complications any day. “Whether it’s anatomical, infection or whatever else, all of that kind of goes to the wayside in this procedure, so that’s pretty appealing from my perspective.”

To Heli & Back

At almost 70 years old, Bob Wislow was still hell-bent on heli skiing—the progressive cartilage degeneration pain from an old football or rugby injury being the only thing holding him back. Once unable to get up and down a ski resort’s lodge stairs, much less ski the hard pack, he turned to mid-ski-trip cortisone shots, an unsustainable solution, doctors warned.

Going the surgical route would mean total knee replacement. But because his “high level of heli-skiing is basically impossible with an artificial knee,” in Wislow’s words, that option was out, too. Enter, Dr. Mitchell Sheinkop in Chicago, a Regenexx affiliate and what Wislow reports being a fairly simple, three-shot procedure. “After that, knee brace for six weeks (first 5-6 days on crutches). After first week, non-weight bearing exercise (like a stationary bike), plus water-walking in a pool,” says Wislow.

As for the skiing? “While I am still a bit careful in the bumps and icy crud, my other skiing (especially my powder skiing) level is totally back,” Wislow reports. “Last season I did my first back-to-back heli trips, skiing really hard in some tricky snow and in some really deep powder—and I really overdid it. While my knees (I had both done last time) were very sore on the last day and slowly improved the week after, I had a simple ‘booster’ shot late that week and was back, full blast, in the gym and on my bike within a few days.”

With a CMH heli trip to British Columbia in the works for starters this season, Wislow’s all set to earn his 3 million vertical foot ski suit. To reach that milestone, he says he’d definitely go back through the Regenexx ritual should the pain return. “This is my second series of this procedure (I had one knee done a few years ago), and it was easier and more effective this time.”

Even with the occasional maintenance, to Wislow, his result is a miracle. “I am back to doing everything I used to do, and so love doing (skiing, long distance road biking, fly fishing in rocky streams) at levels, and for time periods, I wouldn't be able to sustain with an artificial knee,” he points out. “I would recommend a stem cell procedure to anyone considering a knee or hip replacement.”

Dr. Chris Centeno demonstrates how ultrasound is used to guide precision placement of the stem-cells.

Copyright: Heather B. Fried

The Future Stems From...

An out-of-pocket procedure at the moment, Centeno sees too much going on in the stem cell field right now for the non-insurance-coverage situation to stay that way. Supporting that notion, just a decade ago, only a handful of physicians were injecting platelet rich plasma (PRP), which uses blood platelets as a biologic medical product, to heal conditions like tendinopathy. Now there are thousands along with early insurance coverage for certain procedures.

“The same holds true for stem cells, we’re just earlier in that adoption curve. Ten years ago we were the only physicians in the U.S. doing this work, there are now hundreds. This will continue to grow.” If ongoing research happening at the Steadman Philippon Research Institute, associated with Vail’s renowned Steadman Clinic, is any indicator, Centeno is spot on.

In fact, the Steadman-developed microfracture treatment for knee cartilage also appears to have some ACL implications. Also called the healing response, small holes made in the bone near the injury release stem-cell containing blood (among other bio-native materials) that work to form a “super clot,” which becomes the “basis for the new tissue formation,” according to Steadman Clinic’s website.

In the next five years, Centeno predicts that we’ll see cultured stem cells in a vial, in other words, distributable cell drugs, hit the market. In 10 to 15, he sees ACL surgeries dwindling, with the cadaver graft of the future being one that’s stripped of donor cells, coated in the cells of the recipient and then installed—solving the problem of rejection, among other issues.

It gets even crazier. In 20 to 30 years, doctors will be able to hit print, triggering inkjets loaded with cells instead of color cartridges to 3D print layer upon layer upon layer of your own tissue. “So what is truly trashed and can’t be fixed, that [ACL] would be bio printed that is perfect and then tacked down surgically and growth factors will be added to allow it to osteointegrate such that, again, you end up with one that’s in that normal position,” he explains. “So I think that’s probably the thing that’ll replace what we’re doing.”

Centeno sees the present procedure as a middle step on the way there, but one that has the potential to stand the test of time is some ACLs. Tomorrow’s more severe cases will benefit from this futuristic technology, perhaps one day rendering major downtime from debilitating ski injuries a thing of the past.